The present invention is directed to a destructible multi-chambered cartridge for anchoring rods or similar members in boreholes formed in a receiving material A multi-component hardenable mass is provided in the cartridge made up of resin, a hardener and filler members. The trailing portion of the cartridge, relative to the insertion direction into the borehole, has the filler members occupying almost the entire cross-sectional area with the possible addition of the hardener and the remainder of the cartridge is filled with resin and additional filler members.
In view of the advantages, such as the absence of expansion pressure, high static and dynamic load carrying ability and good chemical durability, anchors secured by hardenable masses are utilized at the present time in a considerable portion of all such attachments. There is the disadvantage, however, of such anchorages in that they are not able to carry a load immediately following insertion into a borehole and the hardenable mass tends to run out of boreholes formed in walls or ceilings. To limit such disadvantages resins with a higher viscosity, that is viscous resins, have been used. A problem is that such resins require a great expenditure of effort for mixing the components of the hardenable mass. Moreover, at a certain viscosity, the wetting of the borehole surface with the resin is no longer assured. Since a layer of drilling dust is deposited on the borehole wall and is not bonded by the viscous mass, areas of separation will occur which lead to a reduction in the anchoring values.
An attempt has been made in a known cartridge to prevent the run-out of the resin from the borehole by filling the entire cross-section of the trailing end of the cartridge with filler and hardener. When such a cartridge is inserted into a borehole, the trailing end of the cartridge is located in the region of the opening into the borehole. As a result, due to the concentration of hardener and filler, the hardening or setting process following the destruction of the cartridge in the borehole commences from the trailing end. The completely or partially hardened resin at the trailing end forms a plug for preventing any run-out of the liquid resin from the forward portion of the borehole.
With the hardener being located only in the trailing end portion of the cartridge, it is generally impossible to provide an adequate distribution of the hardener in the resin during the installation operation. As a consequence, the resin requires a long period to set or in the deeper portions of the borehole it does not set at all and there is a detrimental effect on the quality of the anchorage.